1. Field of the Invention
The present invention relates generally to the field of automatic faucets. More particularly, the present invention relates to an automatic faucet having a restricted flow state.
2. Description of the Related Art
Automatic faucets have become popular for a variety of reasons. They save water, because water can be run only when needed. For example, with a conventional sink faucet, when a user washes their hands the user tends to turn on the water and let it run continuously, rather than turning the water on to wet their hands, turning it off to lather, then turning it back on to rinse. In public bathrooms the ability to shut off the water when the user has departed can both save water and help prevent vandalism.
One early version of an automatic faucet was simply a spring-controlled faucet, which returned to the “off” position either immediately, or shortly after, the handle was released. The former were unsatisfactory because a user could only wash one hand at a time, while the latter proved to be mechanically unreliable.
One solution was the hands-free faucet. These faucets employed a proximity detector and an electric power source to activate water flow without the need for a handle. In addition to helping to conserve water and prevent vandalism, hands-free faucets had additional advantages, some of which began to make them popular in homes, as well as public bathrooms. For example, there is no need to touch the faucet to activate it; with a conventional faucet, a user with dirty hands may need to wash the faucet after washing their hands. In public facilities non-contact operation is more sanitary. Hands-free faucets also provide superior accessibility for the disabled, the elderly, and those who need assisted care.
Other kinds of automatic faucets employ touch-control, in which water flow can be toggled by tapping a part of the faucet, such as a button or the spout.
Because one function of automatic faucets is to save water by shutting off the water flow when it is not immediately needed (without requiring the user to manually turn it off and then on again), it is possible for the user to become confused about the state of the faucet. With a strictly manual faucet, the user uses the presence or absence of a water stream to determine whether the faucet is on. With an automatic faucet, however, the absence of a water stream does not indicate whether the faucet has been manually closed, or whether the electrically operable valve is closed and the manual valve is open.
This uncertainty can have several undesirable effects. For example, it can result in inadvertent activation of water flow, as one may approach or put items in the sink area for certain activities when water flow is not desired. This can be especially problematic with faucets that have a proximity sensor, since water flow can be initiated when the user places a hand or other object in the path of the proximity sensor. Also, in certain applications conservation of power is desirable, making it desirable to turn off the automatic faucet functions. In these applications a user may forget or overlook the fact that the faucet is still in an automatic operation mode due to the absence of water flow. Most of these problems can be especially problematic for users unfamiliar with the automatic faucet's operation, such as visitors, or even new adopters.
Thus, what is needed is an automatic faucet that provides users conspicuous and intuitively obvious feedback to distinguish between a manual off state and an automatic off state. The present invention is directed towards meeting these needs, among others.